Critical infrastructure is a term used by governments to describe critically important infrastructure assets that are essential for the functioning of a society and economy. Examples of recognized infrastructure sectors include Agriculture and Food, Banking and Finance, Chemical, Commercial Facilities, Commercial Nuclear Reactors, Materials and Waste, Dams, Defense Industrial Base, Drinking Water and Water Treatment Systems, Emergency Services, Energy, Government Facilities, Information Technology, National Monuments and Icons, Postal and Shipping, Public Health and Healthcare, Telecommunications, and Transportation Systems. Government agencies and private organization may protect these assets by implementing measures and plans to reduce risk to assets from threats and hazards including war, natural disasters, and terrorism.
Congressional legislation and presidential directives call for a comprehensive national approach for emergency preparedness and response. The Homeland Security Act of 2002 promulgates improved prevention, preparedness, response, recovery, mitigation capabilities and coordination processes across the country. The Homeland Security Presidential Directive (HSPD-5) directs the Secretary of Homeland Security to develop and administer a National Incident Management System, among other actions. The HSPD-8 directive requires a unified all-hazards preparedness that stresses collaboration and coordination at every level of government and in the private sector. The Critical Infrastructure Protection directive (PDD-63) calls for a national effort to assure the security of the increasingly vulnerable and interconnected infrastructure. Such efforts include implementing critical infrastructure programs (CIP), which are information-protection programs to enhance information sharing between the private sector and the government. Government agencies may use CIP to analyze and secure critical infrastructure and protected systems, identify vulnerabilities and develop risk assessments, and enhance recovery preparedness measures.